1. Field
Aspects of embodiments of the present invention relate to a rechargeable battery, and more particularly, to a rechargeable battery having an improved structure of a safety device thereof.
2. Description of the Related Art
Rechargeable batteries can be charged and discharged, unlike primary batteries which cannot be recharged. Low-capacity rechargeable batteries are used for portable compact electronic apparatuses such as mobile phones or notebook computers and camcorders, and high-capacity rechargeable batteries are widely used as a power source for driving a motor of a hybrid vehicle, etc.
Recently, a high-output rechargeable battery using a non-aqueous electrolyte having high energy density has been developed. The high-output rechargeable battery is configured with a high-capacity rechargeable battery by connecting a plurality of rechargeable batteries in series so as to be used for driving a motor for an apparatus requiring a large amount of power, such as an electrical vehicle, etc.
In addition, a high-capacity rechargeable battery generally includes a plurality of rechargeable batteries that are coupled in series, and the rechargeable battery may be formed of cylindrical and/or angular shapes.
The rechargeable battery has a structure in which a terminal connected to an electrode assembly where a positive electrode and a negative electrode are disposed with a separator interposed therebetween protrudes outward.
When gas generated by an electrolytic solution which is decomposed by heat generated from inside of the rechargeable battery causes the internal pressure of the rechargeable battery to be abnormally increased, the rechargeable battery may explode. In order to prevent the rechargeable battery from exploding, when the internal pressure of the rechargeable battery increases to a predetermined value or greater, the rechargeable battery should stop being operated.
For example, a safety device having a structure for cutting off current may be installed between a case and the terminal which protrudes outward in order to stop operation of the rechargeable battery.
However, when components constituting the safety device are assembled by a method such as welding, or the like, an assembly process is complicated, work efficiency is deteriorated, and the production cost of the rechargeable battery is increased.
Further, when the safety device is installed outside of a case, a malfunction may occur due to external foreign materials and the like, or the foreign materials may be input into the case.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.